Pile shell boot and mandrel plug point assembly



July 13, 1965 J DQUGHERTY 3,194,022

PILE SHELL BOOT AND MANDREL PLUG POINT ASSEMBLY Filed April 21. 1961 2 Sheets-Sheet 1 INVENTOR. JoH/v J DouqHERTY HTTORN y 13, 1965 J. J. DOUGHERTY 3,

PILE SHELL BOOT AND MANDREL PLUG POINT. ASSEMBLY Filed April 21. 1961 i 2 Sheets-Sheet 2 J' Jv 2;; F r- 1 INVENTOR. JOHN J: DouqHERTY fa /j.

HTTOR United States Patent 3,194,022 FILE SHELL BOOT AND MANDREL PLUG POINT ASSEMBLY John J. Dougherty, Cedar Grove, NJ. (262 Rutherford Blvd, Clifton, NJ.) Filed Apr. 21, 1961, Ser. No. 104,579 1 Claim. (Cl. 61-53) This invention relates generally to the art of piling and more particularly to a pile shell boot and mandrel point assembly that is adapted to drive a pile shell and at the same time initially to center the mandrel in the shell and to maintain the mandrel centered through the driving operation.

In driving a pile section down into the soil with ordinary mandrels, there is a tendency for the bottom of the mandrel to vibrate against the side of the shell section and damage and tear the side of the shell section permitting sand and water to enter the shell section whereby the mandrel becomes jammed in the shell with consequent loss of time and money to extract the mandrel.

Many expedients have been resorted to in order to solve this problem. Despite all such expedients, however, the cost of extracting such mandrels runs into thousands of dollars per year so that the problem has not by any means been solved. The fact remains that a mandrel operating at high speeds will necessarily so vibrate the shell section as to cause 'wear and tear thereupon, and my present invention has as its primary object the provision of a pile shell boot and mandrel point assembly by virtue of which the vibratory forces and impact shocks created by the operation of the mandrel in the shell section will be so controlled or will be directed into the center of the shell section so as to counteract so far as possible the bad effects of these forces upon the shell section.

Another object of the present invention is to provide a pile shell boot and a mandrel point assembly that avoids the disadvantages of prior driving operations by centering the mandrel during its travel whereby uniform driving pressure is brought to bear against the shell and boot and whereby greater penetration is provided.

Another object of the invention is to provide a mandrel plug point that is adapted to fit various shapes of pile shell boots.

Yet another object is to provide a pile shell boot with means for reinforcing the boot.

For further comprehension of the objects and advantages of the invention, reference will be had to the accompanying drawings and the following description taken in connection with the appended claims.

In the accompanying drawings forming a material part of this disclosure;

FIG. 1 is a vertical sectional view through the bottom of a pile shell section and the bottom of a mandrel embodying one form of the present invention.

FIG. 2 is a bottom plan view of the pile shell boot of the assembly.

FIG. 3 is a sectional view taken on the line 3-3 of FIG. 2.

FIG. 4 is a side elevational view thereof.

FIG. 5 is a sectional view taken on the line 55 of FIG. 6.

FIG. 6 is a top plan view of an assembly having a modified form of shell boot and a modified form of mandrel driving end.

FIG. 7 is a view similar to FIG. 5 showing a modified form of pile shell boot and a modified form of mandrel plug point.

FIG. 8 is a bottom plan view thereof.

FIG. 9 is a view similar to FIG. 5 showing an assembly with a modified form of shell boot and a modified form of mandrel driving end.

FIG. 10 is a plan view as seen from the line 1010 of FIG. 9.

FIG. 11 is a view similar to FIG. 8 of an assembly having a modified form of shell boot and a modified form of mandrel point.

FIG. 12 is a view similar to FIG. 4 showing a modified form of shell boot.

Referring in detail to the drawings, in FIG. 1 the bottom end of a pile shell section 31 and the bottom end of a driving mandrel 36 embodying the invention are shown, the mandrel being shown in operative position generally by the reference numeral 15.

inside the shell section. The shell section and mandrel embody a new and useful shell boot and mandrel point assembly.

The novel pile shell boot of the assembly is designated In FIG. 1, the shell boot 15 is shown fastened to the bottom of a pile shell section 31 of the helical type by welding 33.

A conventional driving mandrel 37 of the expansible type with segments 36 and with a helical rib 38 on the outside thereof is shown in driving position on the shell boot 15. The novel mandrel point of the assembly comprises a base-plate 39 on the bottom end of the mandrel and secured thereto by a central tube 35 depending from a block 38. The plate 39 is formed with a solid point 41 welded or secured thereto in any suitable manner. The point 41 is tapered with its base portion secured to the underside of the plate and is of a diameter such as to leave a space between it and the outer periphery of the plate. The segments of the mandrel rest on the plate 39 leaving a space 52 between the segments and the body of the shell section 31.

As shown in FIGS. 2 to 4, inclusive, the novel pile shell boot 15 comprises a frusto-conical hollow body 17 open at the top and coming to a blunt point 19 closure at the bottom. A flat circular flange or plate 21 is formed radially around the periphery of the body. An annular formation 23 is formed on the top surface of the flange 21 around the inner periphery thereof, the outer periphery of the formation 23 being spaced inwardly from the outer periphery of the flange leaving a space 25. Radial ribs 27 are formed on the outer surface of the body 10 extending from the point 19 thereof to the outer periphery of the flange 21. Four such ribs are shown. These ribs stiffen and reinforce the shell boot body.

As shown in FIG. 1, the flat bottom of the block or plate 39 of the mandrel rests upon the flat upper surface of the formation 23 on the flange 21 of the shell boot 15, with the tapered point 41 on the plate fitted snugly in the hollow body 17 of the shell boot 15.

During the driving operation, the mandrel 37 rests evenly on the shell boot 15, and its tapered point 41 will strike the bottom of the body 17 of the boot at its center and if it should strike the body 17 at the side, the tapered point 41 will be forced toward the center In other words, the mandrel and its point 41 will be automatically centered during the driving operation. The clearance provided by the space 52 permits the mandrel to expand within reasonable limits without damage to the shell section.

In FIGS. 5 and 6, a modified form of pile shell boot 15' is shown. In this form, the body 17' is inverted conical in shape, opening at the bottom and blunt point at the closed top 19' as viewed in FIG. 5. An annular formation 23 on the annular flange 21' of the body at the juncture of the body and the flange i dimensioned so as to leave a space 25' at the periphery of the flange. Spaced reinforcing ribs 27' extend along the bottom surface of the flange 21' and on the inner surface of the body 17'. The body 17' extends into a similarly shaped recess 54 in the circular block or plate 39' suitably fastened to the bottom of the mandrel 37'. The bottom flat surface of the block or plate rests upon the flat top surface.

of the formation 23 for driving the boot 15 into the soil. The modified form of shell boot'15 shown in FIGS. 7 and 8 differs from the form of FIG. 1 merely in that the body17 is solid with a centralsquare-shaped recess 45 to receive a similarly shaped protuberance 41 on the plate 39 constituting a modified point of the mandrel 37 In FIGS. '9 and 10, another modified form of assembly is shown comprising a modified formvof shell boot .having a'flat circular plate-like body'17" with a circular like body, a circular enlargement on the top surface of having theirlower edges disposed in a plane parallel to V the under surface of the plate-like body, and a base plate formation 23" on the top'surface thereof, leaving a pe- I ripheral space 25". Spaced horizontal reinforcing ribs 27" are formed on the under surface of the body. A 7

central upstanding post 47 square in cross-section is formed integrally with the plate-like body and is adapted to be received in a similarlyshap ed recess in the base plate 39" of the mandrel. 1

The modified form of assembly shown in FIG. ll is the same asthe form of FIGS. 7 and 8, except that the boot 15x is hexagonal in configuration, and the mandrel point 41x-on the base plate 39x is hexagonal. 1

The modified form of shell boot '15xx shown in FIG.

12 is similar to the form of shell boot 15 of FIG. 1' except: 7

that no ribs 27 are shown. This boot 15xx is to be used with a mandrel point such as the point 41 of FIG. 1.

In an emergencyfa sleeve may be slipped over the 1 shell section 31 and seated on flange 21 as shown in'FIG. r

1 when the soil is tough and the driving is hard.

While I have illustrated and described the preferred embodiments of my invention it will be understood that changesin details of construction might be made without departing from the principle of theinv ention and desire of the'prior art and'the to be limited only by the state app nded claims.

I claim:

on the driving end of a mandrel body, said base plate having a'recess of a shape and dimension fitting snugly about the upstanding post with the lowermost surface of said 'base plate resting upon the enlargement of the boot.

References Cited by the Examiner UNITED STATES PATENTS 226,237 4/80 Maclay 61-53 7 869,336 10/07 Stew-art 61-53.7 973,887 /10 Steinmetz 61-53 980,436 1/11' Pruyn -2 61-53.7 j 1,342,424 "6/20 Cotton 17'5--19 X 1,847,853 3/32 Watt 61--53.72 -1,908,217 5/337 Blumenthal 61-53.5 1,912,108 5/33 Upson Q. 61-53.7 1,951,643 3/34 Bald 61 53 2,184,514 12/339. Cleesattel -2 61-53.6 2,323,772 7/431. Hood 6153.6 3,075,358 l/63 Becker et al 6153 FOREIGN PATENTS a 370,838 3/23 Germany. 475,874 a 3/27 Germany. 87,7 12 Ill/'36 Sweden.' 7

CHARLES E. OCONNELL, Primary Examiner.

' JACOB L.NACKENOFF, JACOB SHAPIRO,

I T Exa ne 

